A long long time ago in a totally new dimension businesses used to generate leads, by sending out surveys in the mail (The one that used to get delivered to your house), or having you fill out a form. But in an instance the Internet completely changed the way one got leads.
Today the advantage for startups is that they already know the value when it comes to social media and so they are able to write quality gated content, video marketing using live action or animation, email and paid ad campaigns that create “funnel effect” which helps consolidating market base getting more customers. It is quicker and more importantly easier to track the data you collect which is so important to create long term strategy.